For aftertreatment of exhaust gases of an internal combustion engine it can be required to introduce a liquid reactant into the exhaust gas flow. It can be required, for example, to introduce water or fuel into the exhaust gas flow. However, so-called SCR-systems, SCR standing for “selective catalytic reduction”, are of particular interest. With such an SCR system, attempts are made with the help of a reduction agent to reduce harmful nitrogen oxides contained in the exhaust gas to harmless nitrogen. A possible reduction agent in this case is ammonia. This is generally introduced into the exhaust gas flow in the form of a watery urea solution. Through thermolysis and hydrolysis, an efficient mixture of ammonia and carbon dioxide is created from this, which makes it possible in conjunction with an SCR-catalytic converter, to convert nitrogen oxides into nitrogen and water. In order for the respectively desired reaction to take place as efficiently as possible, extensive evaporation of the introduced liquid reactant and as homogeneous as possible a mixing-through of the reactant with the exhaust gas flow is required. For this purpose, stationary mixers are employed which are installed in a housing of the exhaust gas treatment device, specifically with respect to the exhaust gas flow downstream of an injector for introducing the reduction agent.
Since the exhaust gases of an internal combustion engine, depending on the operating state, can reach relatively high temperatures, efficient fixing of the mixer in the housing is required. Furthermore, exhaust gas treatment devices are products which are produced within the scope of large series. To this end, the construction of the exhaust gas treatment device has to be realizable as cost-effectively as possible.